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https://issues.apache.org/jira/browse/HIVE-14165?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15767455#comment-15767455
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Sahil Takiar commented on HIVE-14165:
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[~poeppt] just attached an RB.
I agree we shouldn't make backwards incompatible changes to Hive. Let me know
what you think of the RB.
There are some alternatives to this approach though:
* The file listing could be done in the background, by a dedicated thread
* Listing could be done eagerly rather than lazily so that the file listing
does not block the fetch operator
This would offer a good speedup, but would require the same amount of metadata
operations to S3.
> Remove Hive file listing during split computation
> -------------------------------------------------
>
> Key: HIVE-14165
> URL: https://issues.apache.org/jira/browse/HIVE-14165
> Project: Hive
> Issue Type: Sub-task
> Affects Versions: 2.1.0
> Reporter: Abdullah Yousufi
> Assignee: Sahil Takiar
> Attachments: HIVE-14165.02.patch, HIVE-14165.03.patch,
> HIVE-14165.04.patch, HIVE-14165.05.patch, HIVE-14165.06.patch,
> HIVE-14165.patch
>
>
> The Hive side listing in FetchOperator.java is unnecessary, since Hadoop's
> FileInputFormat.java will list the files during split computation anyway to
> determine their size. One way to remove this is to catch the
> InvalidInputFormat exception thrown by FileInputFormat#getSplits() on the
> Hive side instead of doing the file listing beforehand.
> For S3 select queries on partitioned tables, this results in a 2x speedup.
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